14 lines
419 B
Perl
14 lines
419 B
Perl
sub binary_search {
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my ($array_ref, $value, $left, $right) = @_;
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return -1 if ($right < $left);
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my $middle = int(($right + $left) >> 1);
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if ($value == $array_ref->[$middle]) {
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return $middle;
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}
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elsif ($value < $array_ref->[$middle]) {
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binary_search($array_ref, $value, $left, $middle - 1);
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}
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else {
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binary_search($array_ref, $value, $middle + 1, $right);
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}
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}
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